Limits on Universality in Ultracold Three-Boson Recombination

Abstract

The recombination rate for three identical bosons has been calculated to test the limits of its universal behavior. It has been obtained for several different collision energies and scattering lengths a up to 105 a.u., giving rates that vary over 15 orders of magnitude. We find that universal behavior is limited to the threshold region characterized by E≲ℏ2/2μ12a2, where E is the total energy and μ12 is the two-body reduced mass. The analytically predicted infinite series of resonance peaks and interference minima is truncated to no more than three of each for typical experimental parameters.